WO2010092881A1

WO2010092881A1 - Data recording device, data reading device, tape drive, method of recording data, and method of reading data

Info

Publication number: WO2010092881A1
Application number: PCT/JP2010/051236
Authority: WO
Inventors: 浩板垣; 敏幸白鳥
Original assignee: インターナショナル・ビジネス・マシーンズ・コーポレーション
Priority date: 2009-02-10
Filing date: 2010-01-29
Publication date: 2010-08-19
Also published as: CN102308336B; EP2398020A4; US8824080B2; US20130003212A1; US9230600B2; EP2398020A1; JP5199401B2; US20120014014A1; CN102308336A; JPWO2010092881A1

Abstract

A method of recording data onto a tape medium, facilitating management of a plurality of inter-related data. First data (41) and second data (42) continuously received as one file from a higher level device are stored in a plurality of buffer segments as a continuous plurality of data sets (51), and the data configurations of the stored data sets (51) are determined. Further, management information showing the determination results is added to the data sets (51), and the data sets (51) and the management information (52) are stored in the tape medium.

Description

Data recording apparatus, data reading apparatus, tape drive, data recording method, and data reading method

The present invention relates to an apparatus, a method, and the like for writing data on a tape medium such as a magnetic tape.

In a tape drive that writes data to a tape medium such as a magnetic tape, as shown in Patent Documents 1 to 3, etc., a plurality of mutually related data is temporarily stored in a buffer, and data is transferred from the buffer to the tape medium at a predetermined timing. Is generally written. For example, when the tape drive receives a data file and a metadata file representing the contents of the data from the host device, the tape drive temporarily stores these two files in the buffer and writes them from the buffer to the tape medium at a predetermined timing.

JP 2007-73108 A JP 2007-95231 A JP 2007-241897 A

However, since the data file and the metadata file are transmitted from the host device as two independent files, the conventional tape drive continuously stores main data and sub-data representing the contents of the main data on the tape medium. Although it can be stored, it has not been possible to determine whether each piece of continuously stored data is related to each other like main data and sub data. Therefore, when a tape medium storing main data and sub data is moved to another system or restored to the same system, the contents of the data read from the tape medium are analyzed by an application program on the system, and the main data and The association could not be determined without checking the sub-data association.

The present invention has been made to solve the technical problems as described above, and its purpose is to move to other systems in the future when a plurality of data related to each other is recorded on a tape medium, Or, even when restoring to the same system, it is possible to always store and retain a plurality of related data in the same location, and to identify each data when reading from the tape medium. There is to do.

For this purpose, the data recording apparatus of the present invention is a data recording apparatus for storing first data and second data related to the first data on a tape medium, and is continuously recorded as one file from a host apparatus. A plurality of buffer segments that sequentially store the first data and the second data received in a predetermined size as one or more continuous data sets of a predetermined size, and a determination for determining a data configuration of the data sets stored in the buffer segments Means, management information addition means for adding management information indicating the result of determination by the determination means to the corresponding data set, the data set stored in the buffer segment, and the management information added to the data set Storage control means for controlling storage on the tape medium.

The method is a data recording method for storing first data and second data related to the first data on a tape medium, the first data continuously received as one file from a host device, and A step of sequentially storing the second data in a plurality of buffer segments as one or more continuous data sets of a predetermined size; a step of determining a data configuration of the data set stored in the buffer segments; and a result of the determination And a step of controlling the storage of the data set accumulated in the buffer segment and the management information added to the data set to the tape medium. .

According to the data recording apparatus and method of the present invention, the first data and the second data continuously received as one file from the host apparatus are stored in the buffer segment as one or more continuous data sets of a predetermined size. The data structure of the accumulated data set is determined. Then, management information indicating the discrimination result is added to the corresponding data set, and the data set and the management information are stored in the tape medium. Therefore, since the first data and the second data are recognized as the same file in the data storage device, the first data and the second data are moved to different locations in the future and are not stored separately. On the other hand, since the data storage device can identify the first data and the second data based on the management information, only the necessary information can be read on demand or by default.

Further, in the data recording device, the determination unit detects switching of data stored in the buffer segment based on a predetermined request from the host device, and data of the data set based on the detection result It can also be a means for discriminating the configuration. With such a configuration, the host device may output a predetermined request to the data recording device in order to switch the data stored in the buffer segment, so that the host device outputs the request to the data recording device. There is an advantage that it is not necessary to change the data structures of the first data and the second data, and the change of the software of the host device can be reduced.

Further, in the data recording device, the buffer segment is configured to accumulate invalid data in the empty area and complete the data set when the determination unit detects switching of data accumulated in the buffer segment. It can also be configured. With such a configuration, it is possible to prevent the first data and the second data from being mixed in the data set.

Further, in the data recording apparatus, the determination unit may change the configuration of the data set to the first data, the second data, the first data, and the data based on a detection result of data switching stored in the buffer segment. It may be a means for discriminating one of the mixed data composed of the second data. With such a configuration, there is no need to write invalid data on the tape medium, and there is an advantage of saving tape capacity.

Furthermore, in the data recording apparatus, the management information may be a management table for the data set. With such a configuration, an existing management table such as DSIT (Data Set Information Table) of the LTO standard can be diverted. Therefore, in order to realize the present invention, addition to the existing configuration is the minimum necessary. It can be.

In the data recording apparatus, the management information adding unit includes the first data and the second data when the data set is configured by including both the first data and the second data. The data size can be added to the management information and added to the data set. With such a configuration, it is possible to confirm the data sizes of the first data and the second data that constitute the data set based on the management information. Therefore, the first data and the second data are mixed in the data set. In addition, necessary data can be extracted from the data set based on the management information.

Further, in the data recording device, the management information adding means obtains file version data corresponding to the data set stored in the buffer segment from the host device, and the management information having the file version data is obtained from the data set. It can also be a means to be added to. With such a configuration, a plurality of versions of one file can be stored together on a tape medium.

Furthermore, in the data recording apparatus, the management information adding means acquires password data corresponding to the data set stored in the buffer segment, and adds the management information having the password data to the data set. You can also With such a configuration, a password can be set in the management information for each data set. Therefore, when the data set is read, if the management information matches the password specified by the user, the data set is set. If reading and the password do not match, reading of the data set can be prohibited. Therefore, it can be stored on the tape medium by distinguishing between a part that can be read only by a person who knows the password and a part that can be generally read.

Further, the data recording apparatus may include a controller that functions as the determination unit, the management information addition unit, and the storage control unit. With such a configuration, the determination unit, the management information adding unit, and the storage control unit can be realized by a single controller, so that the configuration of the apparatus can be simplified.

For this purpose, the data reading device of the present invention is a data reading device that reads data in units of data sets from a tape medium that records first data and second data related to the first data as one file. Reading means for reading the data set and the management information added to the data set from the tape medium, and the data structure of the data set corresponding to the read management information is predetermined transfer target data Whether or not based on the management information that has been read, and the first data that has been determined that the read determination means is data to be transferred among the data constituting the data set; Transfer means for transferring at least one of the second data to a transfer destination.

The method is a data reading method of reading data in units of data sets from a tape medium that records first data and second data related to the first data as one file, the data set and the data The management information added to the set is read from the tape medium, and whether the data configuration of the data set corresponding to the read management information is predetermined transfer target data is the read management Determining based on information, and transferring at least one of the first data and the second data determined to be the transfer target data among the data constituting the data set to a transfer destination, Including.

According to the data reading apparatus and method of the present invention, a data set and management information added to the data set are read from a tape medium, and the data configuration of the data set is transfer target data based on the management information. Determine whether or not. Then, at least one of the first data and the second data determined to be transfer target data among the data constituting the data set is transferred to the transfer destination. Therefore, since the data that is the transfer target data among the data sets read from the tape medium is determined based on the management information and transferred to the transfer destination, the transfer destination analyzes the data contents of the data set. Since it is not necessary, an application program or the like for performing the analysis can be made unnecessary. In addition, since the transfer destination only needs to request reading without considering the relevance of the data, the processing of the transfer destination can be simplified.

Further, in the data reading apparatus, the data reading device has a buffer segment for storing the data set read by the reading unit and its management information, and the reading determining unit is based on the management information stored in the buffer segment. It may be a means for determining whether or not the data of the data set corresponding to the management information is the transfer target data. With such a configuration, the data configuration of the data set can be determined based on the management information added to the data set read to the buffer segment, and the relevance of the data of the read continuous data set can be identified. Therefore, each data of a plurality of data sets can be associated without a dedicated application program.

Furthermore, the data reading device of the present invention is a data reading device that reads data in units of a data set from a tape medium that records first data and second data related to the first data as one file. Management information reading means for reading management information added to the set from the tape medium, and whether the data of the data set corresponding to the read management information is predetermined target data or not Target data determination means for determining based on information, and among the data constituting the data set, the target data determination means is located at the requested data position based on a plurality of data determined to be target data And a data detecting means for detecting data.

The method is a data reading method for reading data in units of data sets from a tape medium that records first data and second data related to the first data as one file, and is added to the data set. The management information is read from the tape medium, and whether or not the data configuration of the data set corresponding to the read management information is predetermined target data is determined based on the read management information. And detecting data located at the requested data position based on a plurality of data determined to be the target data among the data constituting the data set.

According to such a data reading apparatus and method, the management information added to the data set is read from the tape medium, and it is determined whether or not the data configuration of the data set is the target data based on the management information. And the data located in the requested | required data position are detected from the data which determined that it is object data among the data which comprise a data set. Therefore, since it is possible to detect data located at a desired data position from continuous target data read from the tape medium, there is no need for a dedicated application program for associating each data of a plurality of data sets in the host device. can do.

For this purpose, the tape drive according to the present invention is a tape drive including the data recording device according to any one of claims 1 to 9 and the data reading device according to claim 10 or 11. ing.

According to such a tape drive, the data recording device includes the first data and the first data stored in the data set stored in the buffer segment including at least one of the first data and the second data constituting the same file. Management information indicating the data structure of the two data is added and stored in the tape medium. Further, the data reading device transfers the data determined to be the transfer target data to the transfer destination based on the management information added to the data set read from the tape medium. Therefore, since the data configuration of each data can be determined when reading from the tape medium, it is possible to identify the first data and the second data constituting the same one file.

According to the present invention, a plurality of pieces of related data are recorded on the tape medium as the same single file, and therefore, part of the information of the plurality of pieces of related data is lost in the process of data movement or restoration. There is no such thing as being called. In addition, when reading from the tape medium, each data can be identified in the tape drive, so there is no need for the application program on the system to analyze the contents of the data read from the tape medium, and the data is stored on the tape medium. The versatility of the device for writing can be improved.

It is a block diagram which shows an example of schematic structure of the tape drive of this invention. It is a block diagram which shows basic structures, such as a data recording device of this invention, a data reading device, and a tape drive. It is a figure for demonstrating the relationship between the buffer in FIG. 1, and a data set. It is a figure for demonstrating an example of the relationship between a data set and DSIT. It is a flowchart which shows an example of the Write command process which concerns on this invention which the controller in FIG. 1 performs. It is a flowchart which shows an example of the Sync process which concerns on this invention which the controller in FIG. 1 performs. It is a flowchart which shows an example of the ModeSelect command process which concerns on this invention which the controller in FIG. 1 performs. It is a flowchart which shows an example of the data read-out process which concerns on this invention which the controller in FIG. 1 performs. It is a figure for demonstrating another example of the relationship between a data set and DSIT. It is a flowchart which shows an example of the 2nd Write command process which concerns on this invention which the controller in FIG. 1 performs. It is a flowchart which shows an example of the DSIT preparation process which concerns on this invention which the controller in FIG. 1 performs. It is a flowchart which shows an example of the 2nd Sync process which concerns on this invention which the controller in FIG. 1 performs. It is a flowchart which shows an example of the 2nd ModeSelect command process which concerns on this invention which the controller in FIG. 1 performs.

Hereinafter, modes for carrying out the present invention (hereinafter referred to as “embodiments”) will be described in detail with reference to the drawings of FIGS. 1 to 13.

1, the tape medium recording system 1 includes a tape drive 10 and a host computer (host) 20. The tape drive 10 and the host 20 are electrically connected.

The tape drive 10 corresponds to the data recording device 10A and the data reading device 10B shown in FIG. The tape drive 10 includes an interface 11, a buffer 12, a recording channel 13, a tape medium (hereinafter also referred to as a tape) 14a, a head 14b,

reels

14c and 14d, a cartridge 14e, a motor 15, and a head position. A control system 17 and a motor driver 18 are included.

The interface 11 communicates with the host 20. For example, a command for instructing data writing to the buffer 12 or a command for instructing data writing from the buffer 12 to the tape 14 a is received from the host 20. As a communication standard used in the interface 11, SCSI (SmallmComputer System Interface) is exemplified. In the case of SCSI, the former command corresponds to the Write command. The latter command (synchronization command) can be replaced by a WriteFileMark (WriteFM) command. Further, the interface 11 returns a response to the host 20 as to whether the processing according to these commands has succeeded or failed.

The buffer 12 is a memory for accumulating data from the host 20 to be written to the tape 14a. For example, it is composed of DRAM (Dynamic Random Access Memory). As shown in FIG. 3, the buffer 12 includes a plurality of buffer segments (hereinafter also referred to as segments) 12b, and each segment 12b stores a data set 51 that is a predetermined read / write unit for the tape 14a. ing.

As described above, in the present embodiment, the LTO (Linear-Tape-Open) standard is described as an example, and the terminology also conforms to the LTO standard. For example, a group of data stored in one segment of the buffer 12 is expressed as “ Data set ". Then, the segment 12 b accumulates (stores) a plurality of various data from the host 20 as a continuous data set 51.

The recording channel 13 is a communication path used for writing the data set 51 accumulated in each of the segments 12b of the buffer 12 to the tape 14a.

The tape 14a is a tape medium as data recording means, and the data set 51 passed through the recording channel 13 is written to the tape 14a by the head 14b. Further, the tape 14a is wound around the

reels

14c and 14d, and selectively moves in the direction from the reel 14c to the reel 14d or from the reel 14d to the reel 14c in accordance with the rotation thereof. The cartridge 14e is a container for accommodating the reel 14c around which the tape 14a is wound, but a cartridge for accommodating the reel 14d may be provided.

Further, the motor 15 rotates the

reels

14c and 14d. In FIG. 1, the motor 15 is represented by a single rectangle. However, it is preferable that two motors 15 are provided, one for each of the

reels

14c and 14d.

The controller 16 controls the entire tape drive 10. For example, the writing of the data set 51 to the tape 14a is controlled according to the Write FM command received by the interface 11. The head position control system 17 and the motor driver 18 are also controlled. The controller 16 executes a program such as microcode to determine the discriminating means 16a, the management information adding means 16b, the storage control means 16c of the data recording apparatus 10A shown in FIG. 2, and the reading means 16d of the data reading apparatus 10B. It functions as a reading discriminating means 16e and a transferring means 16f.

The head position control system 17 is a system that tracks one or more desired laps. Here, the lap is a group of a plurality of tracks on the tape 14a. When it is necessary to switch the lap, it is necessary to electrically switch the head 14b. Therefore, the head position control system 17 performs such switching control.

The motor driver 18 drives the motor 15. As described above, if two motors 15 are used, two motor drivers 18 are also provided. Here, for convenience of drawing, the motor driver 18 is connected to the controller 16 via the head position control system 17, but may be directly connected to the controller 16.

Next, the host 20 uses a server computer or the like to perform data transfer with the tape drive 10. The host 20 uses the tape drive 10 for backup of programs and various data. When the host 20 requests to write the file data to the tape 14a, the write command is issued together with the data obtained by dividing the file data 4 into a predetermined size smaller than the data set 51, as shown in FIGS. Transmit to the tape drive 10. Note that the file data 4 can be larger than the data set 51 or any size for each data.

Further, the host 20 transmits a Read command to the tape drive 10 when reading data from the tape 14a. In the present embodiment, a case where a SCSI ModeSelect command (hereinafter also referred to as an MS command) is used as a method for specifying a stream ID (hereinafter also referred to as SID) according to the present invention for the tape drive 10 will be described. A dedicated command can be newly provided. As an example of the SID, “1” is defined as Default (main data), and “2” is defined as sub-data. Note that the host 20 is not limited to a computer, and may be various electronic devices such as audio devices and household electric appliances (home appliances).

Next, an example of the relationship between the user data stored in the tape 14a and the data set 51 in the above-described tape medium recording system 1 will be described below with reference to FIG.

4, when sending a plurality of files 4 as a series of user data to the tape drive 10, the host 20 inserts a symbol called a file mark 4 f between each of the plurality of files 4. Thus, the boundary between the plurality of files 4 can be identified. The Nth file 4 shown in FIG. 4 includes main data 41 corresponding to the first data in the claims and sub data 42 corresponding to the second data in the claims. Yes. N represents an integer.

The main data 41 may be arbitrary data such as video, music, and documents. The sub data 42 is data related to the main data 41, and can be, for example, metadata. In the case where the sub data 42 is not associated with the main data 41, the file 4 can be composed of only the main data 41 like the (N-1) th file 4. In the present embodiment, a case where one file 4 is composed of main data 41 and sub data 42 will be described.

It should be noted that the main data 41 and the sub data 42 can be variously different embodiments. For example, in the database, the department information or the like may be the main data 41 and the related personal information or the like may be the sub data 42, and those data may be backed up by the tape drive 10 described above.

A plurality of continuous files 4 are divided according to the transfer size with the file mark 4f interposed. The data set 51 is determined to have an arbitrary data size such as 0x200000 bytes according to the sizes of the buffer 12, the segment 12b, and the like.

The data set 51 is created as any one of the main data 41, the main data 41, the invalid data 43, the sub data 42, the sub data 42, and the invalid data 43. In this embodiment, when the end of the main data 41 or the sub-data 42 of the file 4 is located in the middle of the data set 51, the data after the end is padded with the invalid data 43. Instead of this, various different configurations such as inserting delimiter data and continuously storing the next data after the end may be adopted without performing such padding. In addition, an empty character string or the like can be used as invalid data. In the present embodiment, a case where the data size of the data set 51 is smaller than the data size of the plurality of files 4 will be described. Alternatively, the data size 51 can be an arbitrary data size.

A DSIT (Data Set Information Table) 52, which is a management table, is added to each of the plurality of data sets 51. The DSIT 52 has a data structure indicating the data sequential (DS) number of the data set 51, the number of records in the data set 51, and the like, as used in the LTO standard. In this embodiment, by adding a new field to the DSIT 52, the new DSIT 52 functions as management information in the claims.

DSIT 52 has the SID added to a new field. In the DSIT 52, “1” or “2” is selectively set in the SID according to the data type of the data set 51 or the like. In this embodiment, the SID value is changed in accordance with the MS command from the host 20. Instead, various different configurations may be employed, such as the host 20 specifying the SID value to be changed by a command. The SID can be various data such as a flag and a character, for example, if the main data 41 and the sub data 42 can be selected. Various different embodiments may be employed, such as storing the data set 51 in another area of the buffer 12.

The DSIT 52 is created when user data from the host 20 is divided into data sets 51. The DSIT 52 is added to the data set 51 and stored in the segment 12b of the buffer 12. Instead of this, various embodiments may be adopted in which the DSIT 52 is stored in another area of the buffer 12 in association with the data set 51.

The management information according to the present invention can be realized by adding to the data set 51 or the DSIT 52 as new information such as a flag different from the DSIT 52. However, when the existing DSIT 52 is diverted as in the present embodiment, there is an advantage that changes in the tape drive 10 and its application program can be reduced.

Next, various means when the controller 16 of the tape drive 10 described above functions as the data recording device 10A and the data reading device 10B shown in FIG. 2 will be described.

When the controller 16 functions as the data recording apparatus 10A, the controller 16 functions as the determination unit 16a, the management information addition unit 16b, and the storage control unit 16c shown in FIG. 2 by executing a program.

The determining unit 16a determines whether the data configuration of the data set 51 stored in the segment 12b is the main data 41 or the sub data 42. In the present embodiment, the determination unit 16 a determines the data structure of the data set 51 with reference to the SID value of the memory or the like that is switched in response to a request from the host 20. For example, the discriminating means 16a discriminates the main data 41 when “1” is set in the SID. The discriminating means 16a discriminates the sub-data 41 when “2” is set in the SID. The determination unit 16a can also determine the data configuration by confirming the type of data with the host 20 or analyzing the data content. Further, the determination means 16a may be an embodiment that determines the composite data of the main data 41 and the sub data 42 in addition to the determination of the single main data 41 and the sub data 42 described above.

The management information adding unit 16b adds a DSIT (management information) 52 indicating the result determined by the determining unit 16a to the data set 51. The management information adding means 16b of the present embodiment creates a DSIT 52 having an SID value such as the memory, adds the DSIT 52 to the data set 51, and stores it in the segment 12b.

The storage control means 16c controls the storage of the data set 51 accumulated in the segment 12b and the DSIT 52 added to the data set 51 on the tape 14a. The storage control means 16c of this embodiment controls the recording channel 13, the head position control system 17, the motor driver 18, and the like in order to write the data set 51 and DSIT 52 of the buffer 12 to the tape 14a.

When the controller 16 functions as the data reading device 10B, the controller 16 functions as the reading unit 16d, the reading determining unit 16e, and the transfer unit 16f illustrated in FIG. 2 by executing a program.

The reading unit 16d controls the recording channel 13, the head position control system 17, the motor driver 18, and the like to read the pair of data sets 51 and the DSIT 52 added to the data sets 51 from the tape 14a, and to read the segment 12b. It accumulates sequentially in each of.

The reading discriminating means 16e discriminates whether or not the data of the data set 51 corresponding to the read DSIT 52 is predetermined transfer target data based on the SID of the read DSIT 52 or the like. The read discriminating means 16e according to the present embodiment discriminates whether or not “1” is set in the SID of the DSIT 52 when the transfer target data is the main data 41. Further, when the transfer target data is the sub-data 42, the read determination unit 16e determines whether “2” is set in the SID of the DSIT 52.

The transfer unit 16f uses, as a transfer destination, at least one of the main data 41 and the sub data 42 determined by the read determining unit 16e as data to be transferred among the data constituting the data set 51 accumulated in the segment 12b. The data is transferred to a certain host 20 via the interface 11. That is, when the transfer target data is the main data 41, the transfer unit 16 f transfers the main data 41 of the plurality of data sets 51 to the host 20. Further, when the transfer target data is the main data 41 and the sub data 42, the transfer unit 16f transfers the main data 41 of the plurality of data sets 51 and the sub data 42 continuous to the main data 51 in association with each other to the host 20. .

Next, an example of various processes according to the present invention by the controller 16 of the tape drive 10 described above will be described below with reference to the drawings such as FIGS. First, an example of a write command process executed by the controller 16 when the tape drive 10 receives a write command from the host 20 will be described below with reference to a flowchart shown in FIG.

The controller 16 writes the data received together with the Write command from the position indicated by the pointer of the buffer 12 to the segment 12b (S111). The controller 16 determines whether or not one or more data sets 51 are completed as a result of writing the data to the segment 12b (S112). If the controller 16 determines that one or more data sets 51 are not completed (NO in S112), the controller 16 proceeds to the process of step S115. On the other hand, when the controller 16 determines that one or more data sets 51 are completed (YES in S112), the controller 16 proceeds to the process of step S113.

The controller 16 determines whether the value set in the SID of the memory or the like indicates the main data 41 in the process of step S113, and determines the data configuration of the data set 51. Then, the controller 16 creates the DSIT 52 indicating the determination result, that is, the DSIT 52 having the SID, and then proceeds to the processing of step S114.

In the process of step S114, the controller 16 controls the recording channel 13, the head position control system 17, the motor driver 18, and the like in order to write the data set 51 and DSIT 52 of the segment 12b to the tape 14a via the recording channel 13. Then, the process proceeds to step S115.

In the process of step S115, the controller 16 advances the buffer pointer of the buffer 12 to the end of the data written in the buffer 12, and thereafter ends the process. In the above-described processing, the description has been made on the assumption that the data set 51 including the tail of the data sent by the Write command is normally incomplete. However, if the end of the data fits exactly in the data set 51, the controller 16 will advance the buffer pointer of the buffer 12 to the next segment 12b.

When the controller 16 executes the write command process shown in FIG. 5 described above, the controller 16 functions as the determination unit 16a, the management information addition unit 16b, and the storage control unit 16c in the data recording apparatus 10A in the above-mentioned claims. Become. Specifically, step S113 in the flowchart shown in FIG. 5 corresponds to the determination unit 16a and management information addition unit 16b, and step S114 corresponds to the storage control unit 16c.

Next, an example of the Sync process executed by the tape drive 10 will be described below with reference to the flowchart shown in FIG. The Sync process is a process called from a Mode Select command process to be described later. The Sync process can also be activated by a WriteFM command.

The controller 16 confirms the position of the buffer pointer of the buffer 12 in the process of step S121, and then proceeds to the process of step S122. In step S122, the controller 16 determines whether data remains in the incomplete segment 12b where the buffer pointer is located, that is, whether the buffer pointer is set at the head of the segment 12b. If the controller 16 determines that no data remains (NO in S122), the process ends. On the other hand, if the controller 16 determines that data remains (YES in S122), the controller 16 proceeds to the process of step S123.

In the process of step S123, the controller 16 pads the writable area after the end of the data written in the segment 12b, that is, the writable area of the segment 12b with the invalid data 43, and then proceeds to the process of step S124.

In the process of step S124, the controller 16 determines whether or not the value set in the SID of the memory or the like indicates the main data 41, and determines the data configuration of the data set 51. Then, the controller 16 creates the DSIT 52 indicating the determination result, that is, the DSIT 52 having the current SID, and then proceeds to the processing of step S125. The DSIT 52 created by this processing is composed of main data 41 and invalid data 43. The DSIT 52 indicates by SID that the data set 51 is composed of main data 41.

In the process of step S125, the controller 16 controls the recording channel 13, the head position control system 17, the motor driver 18, and the like to write the data set 51 and DSIT 52 of the segment 12b to the tape 14a via the recording channel 13. Then, the process proceeds to step S126. In step S126, the controller 16 advances the buffer pointer of the buffer 12 to the head of the next segment 12b, and thereafter ends the processing.

When the controller 16 executes the sync process shown in FIG. 6 described above, the controller 16 functions as the management information adding unit 16b and the storage control unit 16c in the data recording apparatus 10A in the claims described above. Specifically, step S124 in the flowchart shown in FIG. 6 corresponds to the management information adding unit 16b, and step S125 corresponds to the storage control unit 16c.

Next, an example of ModeSelect command processing executed by the controller 16 when the tape drive 10 receives an MS command from the host 20 will be described below with reference to the flowchart shown in FIG.

In the process of step S131, the controller 16 compares the current SID of the memory or the like with the SID specified by the MS command, and then proceeds to the process of step S132. In the process of step S132, the controller 16 determines whether or not the SID specified by the MS command is different from the SID of the memory or the like. If the controller 16 determines that the specified SIDs are not different, that is, the SIDs match (NO in S132), the controller 16 does not need to change the SID of the memory or the like, and thus ends the process. On the other hand, if the controller 16 determines that the SIDs are different (YES in S132), the controller 16 proceeds to the process of step S133.

In the process of step S133, the controller 16 calls the sync process shown in FIG. 6 described above, and proceeds to the process of step S134 in accordance with the end of the sync process. In step S134, the controller 16 updates the current SID stored in the memory or the like to the SID specified by the MS command, and then ends the process.

Next, an example of the data read process according to the present invention by the controller 16 of the tape drive 10 described above will be described below with reference to the drawing of FIG. This data reading process is assumed to be executed when the controller 16 receives a Read command from the host 20.

First, the controller 16 acquires a Read command from the host 20 via the interface 11 (S201). The controller 16 sequentially reads the data set 51 and its DSIT 52 from the tape 14a via the recording channel 13 and sequentially stores them in the segment 12b of the buffer 12 (S202), and then proceeds to the processing of step S203.

The controller 16 compares the DS number of the DSIT 52 with the DS number of the continuous DSIT 52 to confirm that the data set 51 is read in the correct order, and the data of the data set 51 is based on the SID of the DSIT 52. Then, it is determined whether or not the transfer target data is requested by the Read command (step S203). Specifically, based on the transfer target data specified by the Read command from the host 20 (for example, SID = "1" or "2"), it is determined whether or not the data in the data set 51 is the transfer target data. Determine. As for the method for requesting transfer target data, various different embodiments may be adopted, such as storing the transfer target data in the built-in memory or the like in advance.

The controller 16 transfers the data of the data set 51 determined as the transfer target data to the host 20 through the interface 11 in the order of the DS number, and ends the processing in response to the end of all the transfers (steps). S204).

When the controller 16 executes the data read process shown in FIG. 8 described above, the controller 16 functions as the read means 16d, the read discriminating means 16e, and the transfer means 16f of the data read device 10B in the claims described above. . Specifically, S202 in the flowchart shown in FIG. 8 corresponds to the reading unit 16d, step S203 corresponds to the reading determining unit 16e, and step S204 corresponds to the transfer unit 16f.

Next, an example of the operation (action) of the tape drive 10 and the host 20 in the above-described tape medium recording system 1 will be described below with reference to the drawing of FIG.

[When writing data]
For example, when backing up a plurality of files 4 to the tape 14a, the host 20 inserts a file mark 4f between each of the plurality of files 4, divides the continuous data into the predetermined size, and writes a Write command or a WriteFM. It is sequentially transmitted to the tape drive 10 together with the command. The host 20 then transmits a Write FM command for a request for synchronization processing to the tape drive 10 at a predetermined timing.

When receiving the first Write command, the tape drive 10 sets “1” as an initial value to the SID of the internal memory or the like. Thereafter, after receiving a plurality of Write commands, the tape drive 10 determines the data configuration of the data set 51 based on the SID of the internal memory or the like when the data set 51 is completed in the segment 12b of the buffer 12. The tape drive 10 creates a DSIT 52 indicating the determination result, and adds the DSIT 52 to the data set 51. When receiving the WriteFM request, the tape drive 10 controls the recording channel 13, the head position control system 17, the motor driver 18, and the like, and starts storing the data set 51 and the DSIT 52 on the tape 14a. .

Thereafter, the tape drive 10 repeats the series of processes described above, so that each time the data set 51 is completed, the data configuration is determined, and a DSIT 52 indicating the determination result is created and added. Then, the tape drive 10 stores the data set 51 and the DSIT 52 added to the data set 51 on the tape 14a.

As shown in FIG. 4, when the data set 51 is completed in the segment 12b of the buffer 12 in response to the write command for the data spanning the (N−1) th and Nth data, the tape drive 10 is based on the SID of the built-in memory or the like. Thus, the data configuration of the data set 51 is determined. Since the SID is “1”, the tape drive 10 determines that the data configuration of the data set 51 is the main data 41 and creates a DSIT 52 indicating the determination result.

For example, as shown in FIG. 4, “1” is set to the SID in the DSIT 52 in which the sequential “16” is set to the DS number. The data set 51 includes the (N−1) th and Nth main data 41 and a file mark 4f. In the DSIT 52 with the DS number “17”, “1” is set as the SID. The data set 51 includes only the Nth main data 41.

Thereafter, when the host 20 detects the end of the main data 41, that is, the separation of the main data 41 and the sub data 42 in the Nth file 4, the host 20 sends the data corresponding to the end of the main data 41 and the Write command to the tape drive 10. After that, the MS command is transmitted to the tape drive 10 in order to change the SID from “1” to “2”.

In response to the Write command, the tape drive 10 stores the data in the segment 12b of the buffer 12. When the MS command is received at that time, the tape drive 10 pads the currently accumulated segment 12b with the invalid data 43 so that the data Complete the set 51. A corresponding DSIT 52 is created and added to the data set 51, and then the SID of the memory or the like is changed from “1” to “2”. In this case, the DS number of the completed DSIT 51 is “18”, and the SID is “1”.

Next, the host 20 transmits data obtained by dividing the sub data 42 in the Nth file 4 to the tape drive 10 together with the Write command. On the other hand, when the tape drive 10 receives the Write command and completes the data set 51 in the segment 12b of the buffer 12, the tape drive 10 determines the data configuration of the data set 51 based on the SID of the internal memory or the like. Since the SID is “2”, the tape drive 10 determines that the data configuration of the data set 51 is sub-data 42 and creates a DSIT 52 indicating the determination result. The tape drive 10 adds the DSIT 52 in which “2” is set to the SID to the corresponding data set 51.

Thereafter, when the host 20 detects the end of the sub-data 42, that is, the boundary between the Nth file 4 and the file mark 4f, the host 20 transmits the Write command and its data to the tape drive 10 and then changes the SID from “2”. In order to change to “1”, an MS command is transmitted to the tape drive 10.

The tape drive 10 stores data in the segment 12b of the buffer 12 in response to the Write command. When the tape drive 10 receives an MS command from the host 20 in a state where the data set 51 is not completed, the tape drive 10 completes the data set 51 by padding the currently stored segment 12b with the invalid data 43. When the tape drive 10 determines that the data configuration of the data set 51 is the sub data 42 based on the SID of the built-in memory or the like, the tape drive 10 creates a DSIT 52 indicating the determination result and adds the DSIT 52 to the data set 51. Thereafter, the tape drive 10 changes the SID of the memory or the like from “2” to “1”.

Thereafter, when the tape drive 10 receives the Write command from the host 20 and completes the data set 51, the SID of the built-in memory or the like is set to “1”. The data 41 is discriminated, and a DSIT 52 (SID = “1”) indicating the discrimination result is created and added to the data set 51. The tape drive 10 repeats the series of processes described above to determine the data configuration of the data set 51 based on the SID value of the built-in memory, etc., and creates a DSIT 52 indicating the determination result to generate the data set 51.

[When reading data]
When the host 20 reads desired data from the tape 14a, the host 20 transmits, for example, a Read command designating a DS number range, SID, and the like to the tape drive 10. Here, a case where only the main data 41 is read in the main will be described. Note that it is not always necessary to specify a DS number or the like in the Read command.

Upon receiving a Read command from the host 20, the tape drive 10 sequentially reads the data set 51 and its management information 52 from the tape 14a, and stores (stores) the rank in the segment 12b of the buffer 12. In this embodiment, when the SID is not specified in the Read command, the tape drive 10 uses data corresponding to a predetermined default value (such as “1” for the main data 41) as the transfer target data. To do.

When the data set 51 is read in the correct order based on the DS number of the management information, the tape drive 10 determines whether the data set 51 is the transfer target data requested by the Read command. The determination is made based on the SID. Then, the tape drive 10 sequentially transfers only the main data 41 as the transfer target data to the host 20 via the interface 11. On the other hand, the host 20 sequentially stores the main data 41 received from the tape drive 10 in a memory, a hard disk device or the like.

Next, when only the sub data 42 is read from the tape 14a, the host 20 transmits a Read command designating, for example, an SID to the tape drive 10. Then, the tape drive 10 sequentially reads the data set 51 and its management information 52 from the tape 14 a and sequentially stores (stores) them in the segment 12 b of the buffer 12. When the data set 51 is correctly read in order based on the DS number of the management information, the tape drive 10 determines the data configuration of the continuous data set 51 based on the SID of each management information, and the interface 11 Only the sub data 52 to be transferred is transferred to the host 20. On the other hand, the host 20 sequentially stores the sub data 42 received from the tape drive 10 in a memory, a hard disk device or the like.

According to the tape drive 10 described above, a plurality of main data (first data) 41 and sub data (second data) 42 continuously received as one file from the host 20 are stored as a plurality of continuous data sets 51. And the data structure of each of the stored data sets 51 is determined. A DSIT (management information) 52 indicating the discrimination result is added to the corresponding data set 51, and the data set 51 and its DSIT 52 are stored in the tape 14a. Accordingly, since the DSIT 52 is added to each of the plurality of data sets 51 stored on the tape 14a, the plurality of related data is handled as one file in the tape drive 10, but the data set 51 is read. For example, the main data 41 and the sub data 42 can be identified by confirming the data configuration of the data set 51 from the DSIT 52 added to the data set 51.

Further, the tape drive 10 reads the data set 51 and the DSIT 52 added to the data set 51 from the tape 14a, and determines whether or not the data in the data set 51 is transfer target data based on the DSIT. To do. Then, at least one of the main data 41 and the sub data 42 determined to be transfer target data among the data constituting the data set 51 is transferred to the transfer destination host 20. Therefore, since the data that is the transfer target data in the data set 51 read from the tape 14 a is determined based on the DSIT 52 and transferred to the transfer destination host 20, the host 20 stores the data contents of the data set 51. Therefore, an application program for performing the analysis or the like can be dispensed with. Further, since the host 20 that is the transfer destination only needs to request reading without considering the relevance of the data, the processing of the transfer destination can be simplified.

Therefore, according to the present invention, the main data 41 and the sub data 42, that is, a plurality of mutually related data are recorded on the tape 14a as the same single file. There is no loss of some of the information in the data. Further, when reading from the tape 14a, each data (main data 41 and sub data 42 in this embodiment) can be identified in the tape drive 10. Therefore, the contents of the data read from the tape 14a are stored on the system. Therefore, the versatility of a device for writing data on the tape 14a can be improved.

In the above-described embodiment, the case has been described in which only the SID is added to the management information DSIT 52 so that the main data 41 and the sub data 42 can be discriminated. However, the present invention is not limited to this. Other data can also be added.

In the N-th file 4 shown in FIG. 4 described above, the case where the main data 41 and the sub data 42 are prevented from being the same data set 51 by the host 20 has been described. On the other hand, the data set 51 can be an embodiment in which the main data 41 and the sub data 42 can be mixed.

For example, as shown in FIG. 9, the DSIT 52 includes various data such as the DS number, SID1, SID1_Length, SID2, SID2_Length, and the like. SID1 indicates the first or one type of data in the data set 51. In other words, when SID1 is set to “1” or “2” as described above, the first data in the data set 51 or the data constituting the data set 51 becomes the main data 41 or the sub data. The data 42 is indicated.

In SID1_Length, the length of the data of SID1 is set. When one type of data is stored, the fixed length is 0x200000, and when mixed (two types), the data length of the first data located at the head Are set respectively. SID2 is data indicating whether or not the data set 51 is composed of two types of data. SID2 is set to be blank when the data set 51 is composed of only one type of data. In the case of SID2, when the data set 51 is composed of two types of data, the type of the second data in the data set 51 is set. In SID2_Length, the length of the second data indicated by SID2 is set.

Thus, by providing the SID1_Length and SID2_Length in the DSIT 52, it is possible to confirm the data sizes of the main data 41 and the sub data 42 constituting the data set 51 based on the DSIT 52. Therefore, even if the main data 41 and the sub data 42 are mixed in the data set 51, necessary data can be extracted from the data set 51 based on the DSIT 52.

Next, an example of various processes according to the present invention by the controller 16 of the tape drive 10 described above when setting the data size in the DSIT 52 will be described with reference to the drawings of FIGS.

First, an example of the second Write command process executed by the controller 16 of the tape drive 10 described above will be described below with reference to the drawing of FIG. The second write command process is basically the same as the write command process shown in FIG.

The controller 16 writes the data received together with the Write command from the position indicated by the pointer of the buffer 12 to the segment 12b (T111). The controller 16 determines whether or not one or more data sets 51 are completed as a result of writing the data to the segment 12b (T112). If the controller 16 determines that one or more data sets 51 are not completed (NO in T112), the controller 16 proceeds to the process of step T116. On the other hand, if the controller 16 determines that one or more data sets 51 have been completed (YES in T112), the controller 16 proceeds to the process of step T113.

In the process of step T113, the controller 16 calls a DSIT creation process shown in FIG. 11 to be described later, and proceeds to the process of step T114 when the DSIT creation process ends. By looping the process of step T113 in this way, even if data of a different SID is already stored in the first data set 51 in which the data sent by the Write command is stored, the correct SID is set. Can be set.

Controller 16 determines whether or not DSIT 52 has been created for each of all data sets 51 in buffer 12 in the process of step T114. If the controller 16 determines that the DSIT 52 has not been created for all the data sets 51 (NO in T114), the controller 16 returns to the process in step T113 and repeats a series of processes. On the other hand, when it is determined that the DSIT 52 has been created for all the data sets 51 (YES in T114), the controller 16 proceeds to the process of step T115.

In the process of step T115, the controller 16 controls the recording channel 13, the head position control system 17, the motor driver 18, and the like in order to write the data set 51 and DSIT 52 of the segment 12b to the tape 14a via the recording channel 13. Then, the process proceeds to step T116. In the process of step T116, the controller 16 advances the buffer pointer of the buffer 12 to the end of the data written in the buffer 12, and thereafter ends the process.

Next, an example of the DSIT process in FIG. 10 executed by the controller 16 of the tape drive 10 described above will be described below with reference to the flowchart of FIG.

In the process of step T121, the controller 16 confirms the SID already set in the DSIT 52 associated with the target data set 51, and then proceeds to the process of step T122. In the process of step T122, the controller 16 determines whether or not one or more SIDs, that is, SID1 or SID2 in FIG.

If the controller 16 determines that one or more SIDs are already set (YES in T122), the controller 16 proceeds to the process of step T123. The controller 16 calculates the amount of data from the end of the data already recorded in the segment 12b to the end of the latest data set 51 (T123), and then proceeds to the process of step T125.

On the other hand, when it is determined that one or more SIDs are not set (NO in T122), the controller 16 proceeds to the process of Step T124. The controller 16 sets the value of the data set size as the data amount of the data set 51 (T124), and then proceeds to step T125.

In the process of step T125, the controller 16 sets at least one of the SID1_Length and SID2_Length of the DSIT 52 with the calculated data amount, and sets the SID portion of the DSIT 52 with the calculated data amount and the current SID described in the memory or the like. Then, the process proceeds to step T126. In the process of step T126, the controller 16 creates a part that is not related to the SID of the DSIT 52, and then ends the process.

Next, an example of the second Sync process executed by the tape drive 10 will be described below with reference to the flowchart shown in FIG.

The controller 16 confirms the position of the buffer pointer of the buffer 12 in the process of step T131, and then proceeds to the process of step T132. In the process of step T132, the controller 16 determines whether data remains in the incomplete data set 51 of the buffer 12. If the controller 16 determines that no data remains in the incomplete data set 51 (NO in T132), the process ends. On the other hand, when it is determined that data remains in the incomplete data set 51 (YES in T132), the process proceeds to step T133.

In the process of step T133, the controller 16 pads the writable area after the end of the data written in the segment 12b, that is, the writable area of the segment 12b with the invalid data 43, and then proceeds to the process of step T134. The controller 16 calls the DSIT creation process shown in FIG. 11 described above, and proceeds to the process of step T135 when the DSIT creation process ends.

In the process of step T135, the controller 16 controls the recording channel 13, the head position control system 17, the motor driver 18, and the like to write the data set 51 and DSIT 52 of the segment 12b to the tape 14a via the recording channel 13. Then, the process proceeds to step T136. In the process of step T136, the controller 16 advances the buffer pointer of the buffer 12 to the head of the next segment 12b of the buffer 12, and thereafter ends the process.

Next, an example of the second ModeSelect command process executed by the controller 16 when the tape drive 10 receives an MS command from the host 20 will be described below with reference to the flowchart shown in FIG.

In the process of step T141, the controller 16 compares the current SID of the memory or the like with the SID specified by the MS command, and then proceeds to the process of step T142. In the process of step T142, the controller 16 determines whether or not the SID specified by the MS command is different from the SID of the memory or the like. If the controller 16 determines that the specified SIDs are not different, that is, the SIDs match (NO in T142), the controller 16 does not need to change the SID of the memory or the like, and thus ends the process. On the other hand, if the controller 16 determines that the SIDs are different (YES in T142), the controller 16 proceeds to the process of step T143.

In the process of step T143, the controller 16 confirms the already set SID with the DSIT 52 of the data set 51 where the buffer pointer exists, and then proceeds to the process of step T144. In the process of step T144, the controller 16 determines whether or not one or more SIDs, that is, SID1 or SID2 in FIG.

If the controller 16 determines that one or more SIDs have already been set (YES in T144), the controller 16 proceeds to the process of step T145. The controller 16 calculates the amount of data from the end of the data already recorded in the segment 12b to the end of the latest data set 51 (T145), and then proceeds to the process of step T147.

On the other hand, when it is determined that one or more SIDs are not set (NO in T144), the controller 16 proceeds to the process of Step T146. The controller 16 calculates the amount of data from the beginning of the data set 51 to the current data position (T146), and then proceeds to step T147.

The controller 16 creates or updates the SID-related part of the DSIT 52 with the calculated data amount and the current SID in the process of step T147, and then proceeds to the process of step T148. In the process of step T148, the controller 16 updates the current SID stored in the memory or the like to a new SID specified by the MS command, and then ends the process.

When the tape drive 10 accumulates the data received together with the Write command from the host 20 in the segment 12b of the buffer 12, the tape drive 10 detects the data configuration and the length of the accumulated data set 51, and creates the DSIT 52. As an example of detecting the data structure and its length, as shown in the flowchart of FIG. 4 described above, the type is determined using the SID stored in the memory or the like of the controller 16 and the length is detected. Various embodiments such as a method of receiving and detecting one of the data lengths from the host 20 with the Write command can be used.

Further, when the tape drive 10 receives the Read command from the host 20 and stores the data set 51 and DSIT 52 read from the tape 14a in the segment 12b, the tape drive 10 refers to the SID1, SID1_Length, SID2, and SID2_Length of the DSIT 51, The configuration of the data set 51 is determined, and the data requested by the Read command is extracted and transferred to the host 20.

By configuring the DSIT 52 in this way, even if the data set 51 is composed of both the main data 41 and the sub data 42, the data configuration and the data length can be determined based on the DSIT 52. As in the embodiment, the host 20 transmits a write command to the tape drive 10 so as to separate the main data 41 and the sub data 42. This eliminates the need to store invalid data 43 on the tape 14a even when there are a large number of sub-data 42, which can contribute to a reduction in the amount of data stored in the tape 14a, and the segment 12b of the buffer 12. The size can be increased.

In the present embodiment, since there are only two types of data, main data 41 and sub-data 42, the DSIT 52 can be configured with one SID. For example, only one main data 41, only one main data 41, only one sub data 42, and data that can identify whether the main data 41 and the sub data 42 are mixed or the like constitute one SID. However, as shown in FIG. 9, by configuring with SID1 and SID2, the order of mixed data can be determined. Further, by increasing the number of data indicating the SID of the DSIT 52 and its length (for example, SID3, SID4,...), More types of data can be mixed in the data set 51.

Further, in the tape medium recording system 1 described above, when it is not known at the time of reading whether or not the sub data 42 is included in the cartridge 14e, such as data movement by the cartridge 14e, the host 20 uses the MS command to A correct SID (for example, 0xFF) is set to the target. In that case, the tape drive 10 performs data transfer to the host 20 while confirming the SID of the next DSIT 52. When the SID of the next DSIT 52 is different from the SID of the DSIT 52 corresponding to the data set 51 currently being transferred, the tape drive 10 transmits a check condition as sense data to the host 20. And it can also be set as embodiment that the host 20 recognizes that SID changed with the sense data. The tape drive 10 is set not to transfer the data set 51 with a blank SID. At this time, the check condition is not reported to the host 20.

Further, in the tape medium recording system 1 described above, the LTO standard Locate / which is a command for moving the read / write head 14b to an arbitrary number of records or the position (logical position) of the file mark 4f from the head of the tape 14a. There is a Space command. When receiving the Locate / Space command, the tape drive 10 described above can detect the data position on the tape 14a and move the head 14b to the position.

For example, a case where the head 14b is moved to a desired record position of the main data 41 using a Locate command will be described. The records are assumed to be one data set 51 for easy explanation. The controller 16 of the tape drive 10 described above functions as management information reading means, target data discrimination means, and data detection means. Then, the host 20 transmits a Locate command specifying the record that is the target data to the tape drive 10.

When the tape drive 10 receives the Locate command from the host 20, the tape drive 10 sets the counter of the built-in memory or the like to 0, and sequentially reads the DSIT 52 from the tape 14a by the management information reading means. The tape drive 10 determines whether or not the SID of the read DSIT 52 is “1”, that is, indicates the main data 41 by the target data determination unit. When the target data discriminating means discriminates that the data is the main data 41, the tape drive 10 increments a counter such as the built-in memory. Then, the tape drive 10 determines whether the counter value matches the record specified by the Locate command by the data detection means. If the tape drive 10 determines that they do not match, the data set 51 is not a record of the target data, so that the next DSIT 52 is determined. On the other hand, if the tape drive 10 determines that they match, the head 14b is moved to the head position of the data set 51 on the tape 14a because the data set 51 is the target data requested by the Locate command. Let It is also possible to add the number of records to the above-described configuration of the DSIT 52 and set the number of records when the tape drive 10 creates the DSIT 52.

A case will be described in which the head 14b of the tape drive 10 is moved to the position of the file mark 4f by the Space command. A file mark count indicating the presence / absence and number of file marks, data position, etc. is added to the configuration of the DSIT 52 described above. Then, when the tape drive 10 creates the DSIT 52, a file mark count is set. Based on the DSIT 52, the tape drive 10 determines the data configuration of the data set 51, that is, the presence or absence of the file mark 4f. When the tape drive 10 determines that the file mark 4f is present, the tape drive 10 detects the data position from the DSIT 52. The tape drive 10 detects the head position of the file mark 4f in the data set 51, and moves the head 14b to the position of the tape 14a corresponding to the position.

Furthermore, the DSIT 52 of this embodiment described above can also add a password using a hash value or the like output through a hash function to the data structure. For example, in the tape drive 10, the management information adding unit 16 b acquires password data corresponding to the data set 51 stored in the segment 12 b from the host 20. The management information adding unit 16b may add the DSIT 52 having the password data to the data set 51. With such a configuration, since a password can be set for each data set 51, the data set 51 is stored in the tape 14a by distinguishing between a part that can be read only by a person who knows the password and a part that can be generally read. it can.

Also, in the DSIT 52 corresponding to the sub data 42, a version of one file can be added to the data structure. With this structure, one file can be stored in the tape 14a for each of a plurality of versions. For example, in the tape drive 10, the management information adding unit 16 b acquires file version data corresponding to the data set 51 stored in the segment 12 b from the host 20. The management information adding unit 16b may add the DSIT 52 having the file version data to the data set 51. With such a configuration, a plurality of versions of one file can be collectively stored on the tape 14a.

It should be noted that the above-described present invention may be realized entirely by hardware or entirely by software. It can also be realized by both hardware and software. The present invention can be realized as a computer, a data processing system, and a computer program. This computer program may be stored and provided on a computer readable medium. Here, the medium may be an electronic, magnetic, optical, electromagnetic, infrared, or semiconductor system (apparatus or equipment), or a propagation medium. Examples of computer readable media include semiconductors, solid state storage devices, magnetic tape, removable computer diskettes, random access memory (RAM), read only memory (ROM), rigid magnetic disks, and optical disks. The Current examples of optical disks include compact disk-read only memory (CD-ROM), compact disk-read / write (CD-R / W) and DVD.

Thus, the above-described embodiments are merely representative forms of the present invention, and the present invention is not limited to the embodiments. That is, various modifications can be made without departing from the scope of the present invention.

DESCRIPTION OF SYMBOLS 1 Tape medium recording system 10 Tape drive 10A Data recording device 10B Data reading device 12 Buffer 12b Buffer segment (segment)
14a Tape medium (tape)
16a Discriminating means 16b Management information adding means 16c Storage control means 16d Reading means 16e Reading discriminating means 16f Transfer means 20 Host 51 Data set 52 DSIT (Management information)

Claims

A data recording device for storing first data and second data related to the first data on a tape medium,
A plurality of buffer segments for sequentially storing the first data and the second data received as a single file from the host device as one or more continuous data sets of a predetermined size;
Determining means for determining a data configuration of the data set accumulated in the buffer segment;
Management information adding means for adding management information indicating the result determined by the determining means to the corresponding data set;
Storage control means for controlling storage of the data set accumulated in the buffer segment and management information added to the data set to the tape medium;
A data recording device including:
The determining means is means for detecting switching of data stored in the buffer segment based on a predetermined request from the host device and determining the data configuration of the data set based on the detection result. The data recording apparatus according to claim 1.
The buffer segment is characterized in that when the determination means detects switching of data stored in the buffer segment, invalid data is stored in the empty area to complete the data set. Item 3. The data recording device according to Item 2.
The discriminating unit is configured to change the configuration of the data set based on a detection result of data switching accumulated in the buffer segment to the mixed data including the first data, the second data, the first data, and the second data. 3. A data recording apparatus according to claim 2, wherein said data recording apparatus is a means for discriminating one of the two.
The data recording apparatus according to claim 1, wherein the management information is a management table for the data set.
The management information adding means sets the data size of at least one of the first data and the second data when the data set includes both the first data and the second data. 2. The data recording apparatus according to claim 1, wherein the data recording apparatus is means for adding to the data set in addition to management information.
The management information adding means is means for acquiring file version data corresponding to the data set stored in the buffer segment from the host device and adding the management information having the file version data to the data set. The data recording apparatus according to claim 1, wherein:
2. The management information adding means is means for generating password data corresponding to a data set stored in the buffer segment and adding the management information having the password data to the data set. The data recording device described in 1.
3. The data recording apparatus according to claim 1, further comprising a controller functioning as the determination unit, the management information adding unit, and the storage control unit.
A data reading device that reads data in units of data sets from a tape medium that records first data and second data related to the first data as one file,
Reading means for reading out the data set and the management information added to the data set from the tape medium;
A determination unit for reading that determines whether or not the data configuration of the data set corresponding to the read management information is predetermined transfer target data, based on the read management information;
Transfer means for transferring at least one of the first data and the second data determined by the read determination means as data to be transferred among data constituting the data set;
A data reading device including:
A buffer segment for storing the data set read by the reading means and its management information;
The determination unit for reading is a unit that determines whether data of the data set corresponding to the management information is the transfer target data based on the management information accumulated in the buffer segment. The data reading device according to claim 10.
A tape drive comprising: the data recording device according to any one of claims 1 to 9; and the data reading device according to claim 10 or 11.
A data recording method for storing first data and second data related to the first data on a tape medium,
Sequentially storing the first data and the second data received as a single file from a host device in a plurality of buffer segments as one or more continuous data sets of a predetermined size;
Determining the data structure of the data set stored in the buffer segment;
Adding management information indicating the determined result to the corresponding data set; and controlling storage of the data set accumulated in the buffer segment and the management information added to the data set on the tape medium. When,
A data recording method including:
A data reading method of reading data in units of data sets from a tape medium that records first data and second data related to the first data as one file,
Reading the data set and management information attached to the data set from the tape medium;
Determining whether the data configuration of the data set corresponding to the read management information is predetermined transfer target data based on the read management information; and A step of transferring at least one of the first data and the second data determined to be the transfer target data to a transfer destination;
A data reading method including: